MEDIUM VOLTAGE
RING MAIN UNIT
SFA-RM up to 17.5 kV
www.alfanar.com
Contents
1 - Introduction4
Introduction to SFA-RM 4
a - SFA - RM Solution 4
b - Quality Management 4
c - Quality Checks and Tests 4
d - Environmental Precision5
2 - SFA-RM in Network6
3 - Application 7
4 - Operating Conditions and Standards8
5 - SFA-RM Range9
6 - Design12
7 - Opoerating Mecahnism14
8 - Interlocking System15
9 - Internal Arc Withstand16
10 - Technical Data Sheet17
11 - Components and Accessories18
A - Components 18
a - Vacuum Circuit Breaker18
b - Three Position Load Break Switch19
c - Cable Testing Compartment20
d - Gas Pressure Indicator20
e - Voltage Presence Indication System20
f - Protection Relays21
B - Accessories 22
a - Operating Handle22
b - IR / PD Windows22
c - Motorization Kit ( LBS / VCB )22
d - Earth Fault Indicator (EFI)23
e - Operation Counter for Load Break Switch Mechanism23
f - CVI Auxiliary Contacts23
g - Gas Pressure Indicator with Contacts23
12 - MV Cable Compartment24
A - Cable Compartment24
B - Bushings24
C - Cable Connector25
13 - Dimensions26
14 - SFA-RM Smart28
A - Introduction 28
B - Overview and Layout 30
C - Control and Measuring 32
D - Remote Terminal Unit 33
a - Overview33
b - Features and Functions34
c - Protocols34
E - Power and Supply 34
12 - Ordering Codes35
Introduction to SFA-RM
A - SFA-RM Solution
SFA-RM units are designed for supplying reliable energy, protecting electrical equipment in secondary distribution
networks up to 17.5 kV. SFA-RM units are the best solution for indoor/outdoor distribution substations. Their compact
design makes them suitable for various network applications such as transformer substations, wind power plants,
industrial zones, etc. SFA-RM SF6 gas insulated units offer the following features:
− Compact design up to 17.5 kV; KEMA type tested
− Switching units sealed in SF6 gas filled stainless steel tank
− High level operator safety and operating reliability
− Embedded cable testing compartment, easy and safe cable testing without cable connection removal
− High quality tank welding, leakage rate of less than 0.1% per year
− Maintenance free unit offering a life expectation of over 30 years
− Smart interlocking padlocking system for maximum operator safety
− Different feeder combinations with switch disconnector and vacuum circuit breaker
− Compatible with SCADA systems for remote control and monitoring
− Motorized options for circuit breakers and switches
− High resistance to pollution and humidity
B - Quality Management
SFA-RM units are produced with an integrated quality system carefully defined for all departments. During each
stage of the manufacturing process we ensure that the SFA-RM units are built perfectly; and comply with the
highest adherence standards. The SFA quality system is ISO 9001:2015 Certified.
C - Quality Checks and Tests
Every SRA-RM unit undergoes routine quality tests and intensive related IEC Standards checks to ensure the
highest quality product. These tests are:
1- Sealing check
2- Gas filling pressure check
3- Opening/Closing speed check
4- Tightness test
5- Rotational torque measurement
6- Partial discharge test
7- Dielectric test
8- Conformity with drawings and diagrams check
9- Resistance measurement
The Quality Control Department prepares a test quality certificate for each unit and records the results for
future accessibility and quality assurance.
4
Introduction to SFA-RM
D - Environmental Precision
Using SF6 gas inside the switchgears contributes to the improvement of the reliability, safety and easy maintenance
of SFA-RM units during its life cycle.
Though the use of SF6 gas in electrical equipment is one of the least harmful environmental emissions for utilities,
some governments require SF6 disposal methods be implemented for gas insulated RMUs at the end of its lifetime.
According to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration,
Evaluation, Authorization and Restriction of Chemicals
(REACH), the approved procedure of treatment includes;
Collection of SF6 on site with industrial waste treatment
equipment
Heating of SF6 at above 1,000°C at partner companies
approved facility, (At these temperatures SF6 starts to
dissociate into reactive fragments, which interact with
appropriate partner chemicals mainly hydrogen and oxygen
to form SO2 and HF.)
Removal of HF and SO2 by passing through a calcium
hydroxide solution
Neutralization of the acids and forming of solid sulfates and
fluorides
SF6 gas can thus be destroyed with a removal efficiency
greater than 99%
Greenhouse Gas
Concentration
(parts per billion)
Concentration
Percentage
CO2
353.10³
60%
CH4
N2O
O3
CFC-11
CFC-12
SF6
17.10³
310
10.5
0.28
0.48
0.002
15%
5%
8%
4%
8%
0.10%
Table 1: Concentration Percentages of Greenhouse Gases
SFA-RM in Network
SFA-RM
(SBBS)
SFA-RM
(SBBS)
SFA-RM
(SBS)
SFA-RM
(SBS)
6
SFA-RM
(SBS)
SFA-RM
(SBS)
SFA-RM
(SBS)
SFA-RM
(SBS)
Applications
SFA-RM units are widely used in the following applications:
A - Infrastructure and buildings: ports, railway
stations, airports, hospitals, schools, hotels, malls,
commercial centers, holiday resorts etc.
B - Industries: water, iron and steel, automotive, oil and gas etc.
C - Energy: wind power plants, solar power
plants, hydro power plants, secondary distribution
networks, transformer substations etc.
D - Special applications: high air pollution
areas, high humidity areas etc.
Operating Conditions and Standards
− SFA-RM has an embedded hermetically-sealed gas tank filled with SF6 gas having minimum pressure
of 1.3 bar.
− The expected lifetime of the product is more than 30 years with leakage rate of less than 0.1 % per year.
− No maintenance or gas refilling is required during the lifetime of the SFA-RM.
− The main busbar and switching compartment has an IP 67 protection degree rating whereas the other sections
of indoor products are rated at IP 41 and the outdoor products are rated IP 54.
Operating Conditions :
• Ambient temperature range from -25 °C to 55 °C
• Altitude range of (0-1000 m)*
• Maximum relative humidity of 100%
SFA-RM fully complies with the following IEC standards used
under general operation conditions for indoor switchgears;
a - Switchgear Standards :
• IEC-62271-1
• Verified lightning impulse withstand voltage
• Maintenance free under indoor ambient conditions
• IEC-62271-200
• Internal Arc Classification of Accessibility
• Type A, Classified type FLR for 21 KA / 1Sec (indoor & Outdoor)
b- Switch-Disconnector Standards:
• IEC-62271-103/102
• Class M1 / E3 / E0
• 1000 CO cycles at rated current and 0.7 p.f.
• 5 times close on fault
c- Circuit Breaker Standards
• IEC-62271-100
• Class M1/E1
• O-0.3 Sec - CO - 3 min - CO cycle
d- Other Standards
• IEC-62255 for electrical relays
• IEC-62271-102 for alternating current earthing switch
• IEC 61243-5 for voltage detection system
*: For 1000+ m please contact alfanar
8
SFA-RM Range
Compact SFA-RM units are excellent solutions for secondary distribution networks. It covers all medium voltage
functions such as connection, supply and protection of MV equipment for different applications.
• SBS 3-Way Compact Indoor Type RMU
SELF POWERED RELAY
17.5 kV
630A
21KA
17.5 kV
200A
21KA
17.5 kV
630A
21KA
CT
EFI
Figure 1: 17.5 kV, 2 ring switches up to 630 A + 1 vacuum circuit breaker up to 630A; front view and single line diagram
• SBS 3-Way Compact Outdoor Type RMU
SELF POWERED RELAY
17.5 kV
400A
21KA
EFI
17.5 kV
200A
21KA
CT
Figure 2: 17.5 kV, 2 ring switches up to 630A + 1 vacuum circuit breaker up to 630A; front view and single line diagram
17.5 kV
400A
21KA
SFA-RM Range
• SBBS 4-Way Compact Indoor Type RMU
SELF POWERED RELAY
17.5 kV
400A
21KA
EFI
SELF POWERED RELAY
17.5 kV
200A
21KA
17.5 kV
200A
21KA
CT
CT
17.5 kV
400A
21KA
Figure 3: 17.5 kV, 2 ring switches / up to 630A + 2 vacuum circuit breakers / up to 630A; front view and single line diagram
• SBBS 4-Way Compact Outdoor Type RMU
SELF POWERED RELAY
17.5 kV
400A
21KA
EFI
SELF POWERED RELAY
17.5 kV
200A
21KA
17.5 kV
200A
21KA
CT
CT
Figure 4: 17.5 kV, 2 ring switches / up to 630A + 2 vacuum circuit breakers / up to 630A; front view and single line diagram
10
17.5 kV
400A
21KA
SFA-RM Range
• SSBS 4-Way Compact Indoor Type RMU
SELF POWERED RELAY
17.5 kV
400A
21KA
17.5 kV
400A
21KA
17.5 kV
200A
21KA
17.5 kV
400A
21KA
CT
EFI
Figure 5: 17.5 kV, 3 ring switches / up to 630A + 1 vacuum circuit breaker / up to 630A; front view and single line diagram
• SSBS 4-Way Compact Outdoor Type RMU
SELF POWERED RELAY
17.5 kV
400A
21KA
EFI
17.5 kV
400A
21KA
17.5 kV
200A
21KA
CT
Figure 6: 17.5 kV, 3 ring switches / up to 630A + 1 vacuum circuit breaker / up to 630A; front view and single line diagram
17.5 kV
400A
21KA
SFA-RM Range
• B Modular
B
17.5kV
630A
17.5kV
630A
Figure 7: 12 kV, one vacuum circuit breaker / up to 630A; front view and single line diagram
• S Modular
S
17.5kV
630A
Figure 8: 12 kV, one ring switch / up to 630A; front view and single line diagram
12
Design
20
19
18
17
16
15
1
14
2
13
3
12
4
5
11
6
7
10
8
9
1
2
3
4
5
6
7
8
9
10
Cable Test Compartment
Gas Tank
Interlocking Latch for Cable Test Compartment
Padlocking Facilities for Load Break Switch
Load Break Switch Operating Mechanism
Padlocking Facilities for Earthing Switch
Vacuum Circuit Breaker
Ring Switch Cable Compartment
MV Cable Fixing Support
Tee-Off Switch Cable Compartment
11
12
13
14
15
16
17
18
19
20
Voltage Presence Indicator
Switch-disconnector Operation (Motor Optional*)
Operation Counter
Circuit Breaker Operation (Motor Optional*)
Operating Latch for Vacuum Circuit Breaker
Protection Relay
Lifting Lugs
Padlocking Facilities for Vacuum Circuit Breaker
Vacuum Circuit Breaker Operating Mechanism
Gas Pressure Indicator
Operating Mechanism
On the front panel of SFA-RM units, the status of the operating mechanisms can be clearly seen from the mimic
diagram (closed, opened, and earthed):
• The operating mechanism triggers the moving contact assembly during the closing action. The opening spring
of circuit breaker mechanism is charged while the closing operation is in process.
• The same mechanism is used for opening the circuit breaker, triggered in the opposite direction. Opening is activated by a latch or a relay.
Figure 9: Circuit Breaker Mimic Diagram
• Earthing contacts are opened or closed with a specific operating shaft. The access hole of the shaft
is covered by a plate, which can be opened if the load break switch or circuit breaker is in open
position, and remains locked when it is in close position
Figure 10: Switch Disconnector Mimic Diagram
Since the operating shafts are directly connected
to status indicators, it is very easy and safe to
understand the position of the switches from the
front panel.
Padlocking facilities are available for preventing
access to the load break switch, circuit breaker
and earthing switch operating shafts.
Figure 11: Switch Disconnector Padlocking Facility
14
Interlocking System
• Accesss to the load break switch, circuit breaker and earthing switch are separated from each other to
enforce safety. The cover for the earthing switch can be opened only if the load break switch or circuit breaker is in an open position.
• Access to the cable compartment is fully interlocked with the earthing switch. Access to the cable comparment
is only possible when the earthing switch is in the close position.
• Access to the earthing switch is only possible when the cable compartment cover is closed.
• The earthing switch can only be accessed after closing the cable testing compartment cover.
Figure 12: Earthing Switch Interlocking
Figure 13: Earthing Switch Closing Operation
• The cable test compartment can be opened only if the earthing switch is in the close position.
Figure 14: Unlocking of Cable Test Compartment
Figure 15: Opening of Cable Test Compartment
Internal Arc Withstand
SFA-RM units are designed to withstand rated short circuit current for 1 second without any danger.
Overpressure in the gas tank due to the internal arc is limited with the help of the bursting disk located at the bottom
of the stainless steel tank.
The internal arc in the cable compartment and the withstand capability of the SFA-RM units have been proven
and verified by CESI laboratories to comply with all clauses of IEC 62271 standards to ensure maximum operator
safety.
Figure 16: A Picture Taken During the Internal Arc Test of 17,5kV SFA-RM
16
Technical Data Sheet
Rated Voltage 17,5 kV
Up to 17,5 kV
Busbar Rating
Up to 630 A
Rated Frequency
50 / 60 Hz
Rated Nominal Current For Ring Switch
Up to 630A
Rated Nominal Current For Tee-off Feeder
200/400 / 630 A
21 kA / 1 Sec
21 kA / 3 Sec
Rated Short Time Withstand Current
Internal Arc Classification
A (FLR) 21kA / 1 Sec (indoor & outdoor)
Rated Filling SF6 Gas Level For Insulation
1,2 bar (absolute)
Minimum Functional SF6 Gas Level
1,1 bar (absolute)
Relative Humidity
100%
IP Class (Gas Tank / Indoor / Outdoor)
IP 67/ IP41 / IP54
Rated Lightning Impulse Withstand Voltage
95 kV-peak
Rated Power Frequency Withstand Voltage
38 kV-rms
Applied Standard
IEC 62271-200
Ring Switch
Feeder (S)
Type of Switch-Disconnector
General purpose, three-positioned
(OPEN-CLOSED-EARTHED)
Electrical Endurance
Switch-Disconnector/Earting
Switch
E3 / E0
Mechanical Endurance
Nominal Current
Short-Circuit Making Current
TEE-OFF
Feeder (B)
M1
Up to 630 A
21 kA (also valid for earthing
switch) 54.6kA Peak
Applied Standard
IEC 62271-103/102
Type of Breaker
Vacuum
Electrical Endurance
E3
Mechanical Endurance
M1
Nominal Current
Short-Circuit Breaking Current
Applied Standard
Up to 630 A
21 kA
IEC 62271-100
Components
A - Vacuum Circuit Breaker
Standard Features
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Complying with the related standard - IEC 62271-100
Contacts are in vacuum tubes and the whole mechanism is in an SF6 gas-filled tank
isolated from climatic conditions
Spring charge hole on the front panel with a spring position indicator
Operating latch for opening or closing operations
Spring operated, stored energy mechanism
Operation independent of operator
Padlocking facility on front panel to prevent unwanted closing operation
Smart mimic diagram indicating the switching status clearly (ON, OFF)
A mechanical numeric indicator counting operation cycles
Colored position indication bar directly connected with operating shaft
Trip coil for initiating the tripping operation via signal from self-powered relay
Shunt trip coils for external tripping
Electrical endurance: E1
Mechanical endurance: M1
Optional Features
•
•
•
•
•
•
Motor operation
For circuit breaker: 24 VDC, 110 VDC or 220 VAC
Communications with intelligent systems (SCADA, DAS, etc)
Auxiliary contacts for position indication
For circuit breaker: 8 NO and 8 NC
For earthing switch: 2 NO and 2NC
Figure 17: Circuit Breaker and Disconnector Assembly
18
Components
B - Three Position Load Break Switch
Standard Features
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Complying with the related standards - IEC 62271-103 and IEC 62271-102
Contacts are in SF6 gas filled tank independent from climate conditions
Three phased and three positioned (ON, OFF and Earthing) switching mechanism
Two separate holes on the front panel for Earthing and Disconnecting functions for safe operation
Spring operated stored energy mechanism
Independent of the operator operation
Padlocking facilities on front panel for both Earthing and disconnecting functions of operation
Smart mimic diagram indicating clearly the switching status (ON, OFF, Earth position)
Colored position indication bar directly connected with operating shaft
Interlocking latch for accessing the cable testing compartment
Switch-disconnector electrical endurance: E3
Switch-disconnector mechanical endurance: M1
Earthing switch electrical endurance: E2
Earthing switch mechanical endurance: M1
Optional Features
•
•
•
•
•
•
Motor operation
For load break switch: 24 VDC, 110 VD
Communicating with intelligent systems (SCADA, DAS, etc)
Auxiliary contacts for position indication
For load break switch: 3 NO and 3 NC
For earthing switch: 2 NO
Figure 18: Switch Disconnector Assembly
Components
C - Cable Testing Compartment
For SFA-RM units; the operator does not need to access the cable compartment for cable testing. SFA-RM units
offer a safe way of cable testing from the easily accessible cable testing compartment on the front panel (Refer to
Figure 17). Operators can simply conduct the cable testing through plug-in type connectors after opening the cover.
The cable test cover is safely interlocked and cannot be opened unless the load break switch is earthed.
Figure 19: Front view of Cable Testing Compartment
D - Gas Pressure Indicator
Gas density is an important operating parameter for SF6 insulated MV
equipment. If the required gas density is not sufficient, safe operation
cannot be guaranteed. On SFA-RM units, a gas pressure indicator is fitted to the tank for providing a reliable warning indication against low
gas levels. The gas pressure indicator has sections to show the minimum
pressure for safe operation.
E - Voltage Presence Indication System
All SFA-RM units are integrated with a voltage presence
indication system. A voltage signal comes from the VPIS
through the voltage divider positioned into the cable
entrance of bushings.
The VPIS can be used to check whether a voltage is present
across the cables.
20
Components
F - Protection Relays
• Overcurrent Protection :
1- 50P/50N Function: Phase/Neutral instantaneous overcurrent
Time of operation is independent from the current of operation flowing through the relay, hence if the phase
current increases more than its determined
value for an equal or greater amount of time
than the specified value, then protection
function activates (trips) and does not reset
itself till the value of the phase drops below
the point of current pick-up.
The function activates at 100% of the preset
input, and deactivates at 95%, where the reset is instantaneous. The accuracy of the operating time is equal
to the present time plus a maximum of 30 ms.
2- 51P/51N Function: Phase/Neutral Time
overcurrent Protection
Figure 20: Protection Functions
A - Definite Time O/C Protection
If the option “Definite time” is selected for the curve setting. In this case, the unit operating time
is set by the parameter “Operating time” so as to trip the fault after a preset specific time setting.
If the unit operates with defined time, the function is activated at 100% of the set tap value,
and it deactivates at 95%. If the unit operates with a curve, the function is activated at 110% of
the set pick-up value, and it deactivates at 100%. The reset is instantaneous in both cases. The activation time
is accurate to ±5% or ±30ms, whichever is greater, of the theoretical activation time. The curves used are IEC
60255-151.
B - Inverse Time O/C Protection (IDMT)
If a curve (e.g. inverse, very inverse or extremely inverse) is selected for the curve setting, the operating time principally depends on the current value which is set through the curve type, and dial
and tap settings.
Accessories
A - Operating Handles
In SFA-RM units, there are two operating handles; the first one is for the operation of the load break switch and the second is for charging the spring of vacuum circuit breaker. The design of the operating handles enables a safe and
easy operation for the user.
Figure 21: Switch Disconnector & Disconnector Operating Handle
Figure 22: Circuit Breaker Spring Charging Handle
B - IR / PD Windows
The SFA-RMU can be optionally equipped with IR & PD windows,
a new feature that complies with the new requirements of the Saudi
Electric Company.
The inclusion of an Infrared inspection window is considered as a very
effective method for maintenance personnel to identify any possible
problems with loose electrical terminations without the need to shut down
the RMU. The window consists of polymer and mesh optics to allow
thermal infrared inspection by employing a broadband media.
The inclusion of a partial discharge window is to facilitate the ability to
measure partial discharge of a live RMU and estimate the expected life of
insulation components.
C - Motorization Kit ( LBS / VCB )
Motors with gearboxes can easily be installed to load break
switch and circuit breaker mechanisms either in the factory
or on-site. A built-in electrical interlocking system prevents
any unintentional operations.
When the unit is installed with the motor mechanism, it can
be used with intelligent systems such as SCADA, DAS, etc.
With the help of a selector switch, SFA-RM units can be
controlled remotely by choosing the remote control option.
22
Figure 23: Motor with Gearbox
Accessories
D - Earth Fault Indicator (EFI)
EFI can also be implemented in SFA-RM units. EFIs help the
operator to find the fault location easily in medium voltage
ring networks.
Earth fault is indicated with a LED flashlight and a flag when
asymmetrical currents are detected in three phase cables.
EFI is fed via either auxiliary supply with internal batteries or
core balance current transformer.
Figure 24: EFI
E - Operation Counter for Load Break Switch Mechanism
In SFA-RM units, implementation of an operation counter for mechanical operation of load break switches is
available as an option.
F - CVI Auxiliary Contacts
To automate voltage indication in SFA-RM Units, auxiliary
contacts could be integrated with CVI units.
This feature makes it suitable for SFA-RM to accommodate
the following:
Absence of voltage applications
· Automation on voltage loss.
· Alarms on voltage loss
· Automatic transfer systems
Presence of voltage applications
· Earth locking on presence on voltage
· Alarms on voltage presence
Figure 25: CVI Auxiliary Contacts
G - Gas Pressure Indicator with Contacts
As an optional feature; a gas pressure indicator with electrical switch
contacts can be implemented.
The gas pressure indicator warns the operator when the gas density
drops below the defined “alarm” level, and can block the operation.
Figure 26: Gas Pressure Indicator
MV Cable Termination
A - Cable Compartment
For safe operations, the cable compartment of SFARM units has an interlocking mechanism for preventing
access to the cable compartment when the earthing
switch is opened.
When the cable compartment is open, closing the load
break switch or circuit breaker is prevented by an
additional interlocking mechanism.
As an option, increasing the depth of the cable
compartment is also possible for a lightning arrester
installation.
The Internal Arc Withstand Capacity of cable
compartment is proven by type tests performed in
KEMA Laboratories.
Figure 27: Sample view of Cable Compartment
B - Bushings
Electrical current is carried from outside to inside the RMU via epoxy bushings ensuring the insulation between
the energized conductor and the tank of RMU. Power frequency and partial discharge tests are conducted to each
bushing used in SFA-RM units.
There are 3 types of bushings on SFA-RM units:
Figure 28: Various Bushing Types
24
Bushing
Type
Application
Applicable
Standard
Interface
Type
Material
Current Rating
Voltage
RMT24
Cable Testing
IEC 60137
-
Epoxy Resin
-
24/50/125kV
RMS24
Load Break (S)
Circuit Breaker (B)
IEC 60137
C
Epoxy Resin
630A, 21kA/1s
24/50/125kV
RMB24
Circuit Breaker (B)
IEC 60137
C
Epoxy Resin
630A, 21kA/1s
24/50/125kV
MV Cable Termination
C - Cable Connectors
The following types of cable terminations are available within SFA-RM units;
Figure 29: “L - Type” Cable Termination Alternatives
Figure 30: “L - Type” Cable Termination Alternatives
Dimensions
SSBS and SBBS 4- Way Compact Indoor Type RMU
1655.00
1500.00
1500.00
160.00
1305.00
160.00
1070.00
935.00
1575.00
17.5 kV, 2 ring switches Up to 630 A + 2 vacuum circuit breakers up to 630 A
1575.00
17.5 kV, 3 ring switches Up to 630 A + 1 vacuum circuit breaker up to 630 A
983.00
SBBS and SSBS 4-Way Compact Outdoor Type RMU
NEW DESIGN
875.0
1850
1690
17.5 kV, 2 ring switches Up to 630A + 2 vacuum circuit breakers up to 630A
17.5 kV, 3 ring switches Up to 630A + 1 vacuum circuit breaker up to 630A
26
950.0
935
1700.0
1680.00
Dimensions
SBS 3 Way Compact Indoor Type RMU
1275.00
The height of
Operating Slot
160.00
1070.00
1500.00
1500.00
933.00
160.00
1200.00
17.5 kV, 2 ring switches Up to 630 A + 1 vacuum circuit breaker up to 630 A
SBS 3-Way Compact Outdoor1300.00
Type RMU
NEW DESIGN
875.0
1290
17.5 kV, 2 ring switches Up to 630A + 1 vacuum circuit breaker up to 630A
950.0
935
1700.0
983.00
1450
Dimensions
B Modular
12 kV, one vacuum circuit breaker / up to 630A
S Modular
12 kV, one ring switch / up to 630A
28
SFA-RM - Smart
Introduction
• SFA-RM – Smart is remotely controllable with an integrated RTU and modem, it is designed to be used
effectively in a medium voltage network and DAS (Distribution Automation System).
• It is self-powered equipment as the CPT (Control Power Transformer) is connected directly to the main bus.
SFA-RM - Smart
• Overview and Layout
1
5
2
6
3
7
4
8
Front View
1
2
3
4
30
Protection Relay
SF6 Gas Indicator
ON & Off Push Buttons
Earth Fault Indicator
5
6
7
8
LV Compartment
L/R Selector Switch
MV Compartment
CVI
SFA-RM - Smart
• Overview and Layout
1
2
3
4
Open Doors View
1
2
3
4
Battery
AC/DC supply and battery charger
RTU with integrated modem and antenna
Cable test compartment
SFA-RM - Smart
• Control and Measuring Function
SFA-RM - Smart has an integrated (RTU) to
provide the capability of remote monitoring and
control via the control center.
Connection between the local RTU and control
center is established over a secured Virtual Private
Network connection (VPN) or through an access
point named “APN”
The exchanged data
• Status information from RTU to data center
• Control signal from control center to RTU
• Analog measurements
Status information from RTU to data center
• Close/Open for each CB/LBS
• Earth status for each circuit
• Lock /Unlock for each circuit
• Selector switch status local/remote
• SF6 Gas pressure low/normal
• Power supply status
• Door open/close
Control command from control center to RTU
• Close/Open for each circuit
• Lock/Unlock for each circuit
Analog measurements
• V_ phase (A,B,C)
• I_ phase (A,B,C)
• Frequency
• Total active power [kW]
• Total reactive power [kVAR]
• Total apparent power [kVA]
32
SFA-RM - Smart
• RTU (Remote Terminal Unit)
A - Overview
The RTU is a device installed at a remote location that collects data, codes the data into a format that is transmittable
and transmits the data back to a central station, or master.
The RTU collects information from the master device and implements processes that are directed by the master.
RTUs are equipped with input channels for sensing or metering, output channels for control, indication or alarms
and a communications port.
1
2
6
3
7
1
2
3
4
5
6
7
Power Supply
CPU Processor
DI Digital Input
DO Digital Output
CT/TV Module
Integrated 3G Modem
Antenna
4
5
SFA-RM - Smart
B - Features & function:
1. Data gathering: collect digital and analog inputs from the RMU’s elements and measuring sensors
2. Processing the received signals with a highly sophisticated logic engineering environment as per IEC61131-3.
3. Reporting and receiving the data from/to control center through one of the available communication ports
4. Record and retrieve event and alarm list
5. Acting as master station for the protection relay
6. Communicate simultaneously on all communication ports
7. Modular extendable RTU
C - Supported Protocols
1 - Tele control protocols: IEC 60870-5-101/ -104
2 - Station bus protocols: IEC 60870-5-101/ -104
3 - IED protocols:
• IEC 60870-5-101/ -103/ -104
• Modbus
• SAT 1703
4 - Electric metering protocol: IEC 62056 (IEC 1107)
5 - Standards GSM/GPRS
6 - GSM frequencies: 850, 900, 1800, 1900 MHz
• Power Supply and Batteries:
The proposed Smart RMU is a self-powered unit, where the Supplied power comes from the CPT (Control Power
Transformer) which is directly connected to the live bus and feeds the AC/DC converter and battery system by
220VAC.
The AC/DC converter and battery system feed all equipment in the LV circuit by 24 VDC including the aux relays,
RTU, modem and trip close motor coils. The batteries are capable of providing sufficient power to buffer the load
for more than 24 hours with up to 120 single operations.
34
Ordering
For easy selection please use table No 4:
Function
Unit Configuration
Ingress Protection (IP)
System Voltage
Load break Switch Rating
Circuit Breaker Rating
Function
Code
Description
MT
Metering
S
Load break switch
B
Circuit breaker
41
Indoor application
54
Outdoor application
17
17.5 kV
12
12 kV
63
630 Amp
40
400 Amp
2
200 Amp
4
400 Amp
6
630 Amp
M
NM
E
NE
Motorized
Non-Motorized
Extensible
Non extensible
Table 3: Code List
Unit
Configuration
Voltage
System
Extensibility
Ingress
Protection
S
B
MT
SBS
12
E
54
SBS
SSBS
SBBS
17
NE
41
54
Table 4: Code Map
Load
Break
Switch
Circuit
breaker
2
63
4
40
6
Motor
Kit
M
NM
Tee-off load
rating 1
Tee-off load
rating 2
T1
T1
T2
T2
T3
T3
T4
T4
T51
T51
Transformer rating (1&2) is applicable only with circuit breaker
• T1<250 KVA
• 3000 KVA < T4 < 6000 KVA
• 250 KVA < T2 <1500 KVA
• T5 > 6000 KVA
• 1500 KVA < T3 < 3000 KVA
1 Please
contact alfanar for further clarification
Example 1: SBS
SBS
12
E
54
63
4
NM
-
T2
Example 2: SBS+S
SBS
12
E
54
63
4
NM
-
T2
S
12
E
54
63
4
NM
-
-
E
54
63
4
NM
-
T2
Example 3: SBS+B+B
SBS
12
B
12
E
54
63
4
NM
-
T3
B
12
E
54
63
4
NM
-
T1
Ordering
Unit
Configuration
36
Voltage
System
Extensibility
Ingress
Protection
Load
Break
Switch
Circuit
breaker
Motor
Kit
Tee-off load
rating 1
Tee-off load
rating 2
Ordering
Unit
Configuration
Voltage
System
Extensibility
Ingress
Protection
Load
Break
Switch
Circuit
breaker
Motor
Kit
Tee-off load
rating 1
Tee-off load
rating 2
Notes
For catalogue soft copy scan QR code
MKT_87106_SFA_Feb18_01
www.alfanar.com